Hello,
I have a new build with oil pressure acting a bit strangely. I suspect a pressure relief valve issue, but I was hoping to get some input.
The engine has less than 300 miles on it, but was assembled over a year ago and unfortunately the build notes were lost in a move so some of this information is coming from someone with poor memory. New crank, new rods, and new HV oil pump(I believe sealed power). The oil pump was gone through, ported/smoothed, and mopar high pressure spring added. I do not have or remember the bearing clearances, but I initially installed Clevite HGX bearings to set everything up on the looser end around .0025(I believe).
Kevco 5qt pan and pickup. 12an lines from block to oil filter/cooler.
Upon initial priming with a drill, I think* I saw 70psi. During break in I was seeing 20psi hot idle, and 45-50psi at 35-4000rpm. Oil pressure did not seem to rise above that, and cold oil pressure was 50 at startup. This pressure was seen on a mechanical gauge. An electric gauge was installed and readings verified.
I dropped the pan and inspected everything. It all looked good, but I decided to swap out main bearings for standard non extra clearance to see if it helped with pressure. Verified rear galley plug was installed, and pulled the pump to verify the inner block plug was installed above it. No real change was seen, and I’m seeing around 55psi max from 2500-5500rpm. Pressure does not rise after 2500rpm. 20-25psi hot idle, and 60 psi cold idle.
Currently running VR1 20w-50. I ran 5w-30 for a short time with very little difference in pressures: maybe 5psi less hot idle.
Cam lobe lift is 377/352 with magnum roller lifters so hopefully not pushing them too high and causing a leak.
What should I be checking next? I do have a box stock melling hv pump sitting here that I am considering installing.
